JPH01159250A - Printer - Google Patents

Abstract

PURPOSE:To reduce a difference of printing density due to a difference in the application amount of ink by forming a protruding part on a position of the same phase as types on the flanged part of an ink roll-side pulley and permitting the protruding part and the types to roll over an ink roll in a contacted state. CONSTITUTION:A drive pulley 9 and a driven pulley 19 are arranged at a specified interval, and a loop-like type belt 14 is stretched across both pulleys. A protruding part 19a is formed on a position of the same phase as types on the flanged part of the driven pulley 19 and fitted to a frame 1 in a freely rotating manner. An ink roll 20 installed on an ink roll shaft 41 in a freely rotating manner rotates, pressing the type part 14a of the type belt 14 and the protruding part 19a formed on the flanged part of the driven pulley 19. Thus ink is applied to the type part 14a. In this way, a difference in the pressure surface of an ink roll by types is moderated and a difference in the printing density due to a difference in the application amount of ink is reduced. Furthermore, an irregularity in the type stopping position during type selection is minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a type-type serial printer using a loop-shaped type belt, and particularly to a serial printer characterized by a pulley on which the type belt is stretched.

[Conventional technology]

Conventionally, in a type-type serial printer using a loop-shaped type belt, the flange shape of the pulley on which the type belt is stretched is as shown in Figure tlK22 (formed in a circle with the same height as the type belt connecting part 14c). As a result, the type 14a protrudes from the flange portion 4a, and the ink roll 20 rolls over and contacts the type 14a to apply ink.

[Problem that the invention seeks to solve]

In the case of such a structure, since the surface pressure of the ink roll differs depending on the printed characters, such as . and 8, for example, the difference in the amount of ink applied causes a difference in print density. Furthermore, in a mechanism in which the ink roll is installed on the driven pulley side, the type belt vibrates immediately after the type is selected, so it depends on the type at the contact position of the ink roll, whether or not there is type, or whether the rotation direction The resistance of the ink roll changes depending on whether it is placed before or after the ink roll or only on one side, and the stopping position of the type changes, resulting in large variations in printing position.

Therefore, in order to solve these conventional drawbacks, the present invention forms a convex portion on the flange part of the ink roll side boob at the same phase as the type, thereby reducing the surface pressure of the ink roll due to the type. The purpose of the present invention is to alleviate the difference, reduce the difference in print density due to the difference in the amount of applied ink, and provide a printer that reduces the variation in the stop position of type when selecting type.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention forms a convex undulation part on the flange part of the ink roll side pulley among the pulleys on which the type belt is stretched, at a position in the same phase as the type. It is constructed so that the raised portion and the type are rolled into contact with the ink roll at the same time.

[Effect]

As mentioned above, since the convex portion is formed at the same phase position as the type on the flange part of the pulley on the ink roll side, the difference in the surface pressure of the ink roll due to the type is reduced to lf'0, and the amount of ink applied is The difference in printing density due to the difference in printing type is reduced, and furthermore, the vibration stop position of the type belt immediately after type selection depends on the type at the contact position of the ink roll, whether there is or is not type there, or whether it is before or after the direction of rotation. Even in the case where the pulley is located only on one side, the influence is alleviated by the convex shape of the flange of the pulley, so the variation becomes small.

〔Example〕

Next, one embodiment of the present invention will be described.

<Schematic Mechanism> FIG. 1 is an exploded perspective view of the printer, FIG. 2 is a schematic configuration diagram of the printer, and FIG. 3 is a sectional view of the switching mechanism. FIG. 4 is a schematic side sectional view. A driving pulley 9 and a driven pulley 19 are arranged at a predetermined interval, and a loop-shaped type belt 14 is stretched between them. The flange portion of the driven boob IJ-19 has a convex portion 19a at the same phase as the type.
is formed and rotatably fitted to the frame 1. 2
is a motor and a bevel gear motor gear 8 is attached. The reduction gear 4 has a bevel gear that meshes with the motor gear 3 and a spur gear that meshes with the transmission gear 5 and has a smaller outer diameter than the transmission gear 5. The selection pawl 7 has a structure that allows it to engage with the drive pulley 9 and the printing switching gear 10, and when it is engaged with the printing switching gear 0, it does not engage with the driving pulley 9 and is not engaged with the driving pulley 9. When it is aligned, it does not engage with the printing switching gear 10 (details will be described later>am).In addition, the selection claw 7 is rotatably attached to the frame 1, and the coil spring 8
During standby, a moment is applied in the direction of the arrow. Furthermore, it engages with the attraction plate 33 of the electromagnet 6. The sun wheel 22 is rotatably attached to the frame 1 and has a gear that meshes with a planetary gear 23 that is rotatably attached to a gear drive pulley 9 that meshes with the transmission gear 5. The detection wheel 24 is fixed to the drive pulley 9 and further rotated to the frame 1 (i
= meshes with the gear of the R-cam 25 installed so that
The detection brush 26 is fixed to the detection cover 27 and is made of a conductive material such as nickel silver. A circuit consisting of a conductive part and a non-conductive part is formed on the surface of the detection wheel 24 that comes into contact with the detection brush 26. The printing drum 12 is the hammer 1
A printing claw part 12a for pushing out the image 3 is held on the circumference, and is rotated by a worm 11 which is rotatably attached to the frame 1 while meshing with the printing switching gear 10. A feed roller 29 is fitted to the paper feed gear 28, and the paper feed gear 28 can mesh with the paper feed drive gear 12b of the print drum 12. The pressing roller 18 is pressed against the feed roller 29 due to the load of elastic deformation of the pressing shaft 21.

The ink roll 20 is rotatably attached to the driven pulley side of the frame 1 and presses against the type belt 14.

Next, a type belt according to an embodiment will be explained.

<Configuration of Type Belt> This will be explained with reference to FIG. 15 and FIG. 1θ. Type belt 14
As shown in FIG. 15, it has a loop shape, and a large number of character parts 14a are individually provided along the circumferential direction at a predetermined pitch on the outer circumferential side, and predetermined character parts 14a are provided along the circumferential direction on the inner circumferential side. A large number of belt parts 14b are provided at pitches. The individual type portions 14a and the belt tooth portions 14b are paired with each other, and the type portions 14a and the monument type portions 14a1 and the belt tooth portions 14b
and the adjacent belt tooth portion 14b are connected to each other by a thin connecting portion 14c. These type belts 14 are made of a stretchable elastic material such as rubber. Type belt 14
is divided into multiple groups for one round. Symbol letters such as r+Jr-J for each group, "0", "1",
...The arrangement of numeric characters for "9" is arranged in the same group.

In one of these embodiments, the type belt 14 has 64 positions 3
(one position is one character), and is divided into two groups, 1 group and
・Displayed as "mouth") Symbols are printed in odd number digits from 1 position to 21st position, and numbers are printed from 22nd position to 31st position to form 1 group. There is. The space is free of type portions 14a and 14b.

As explained in <Schematic Structure>, the type belt 14 is passed between the driving pulley 9 and the driven pulley 19, and the driving pulley 9 and the driven pulley 18 have grooves 16 that mesh with the belt teeth 14b.
It meshes with each of the belt teeth 14b. The type belt 14 is reliably driven with no slippage between the driving pulley 9 and the driven pulley 19. Next, the inking mechanism will be explained with reference to FIGS. 1 and 2.

<Inking mechanism> The ink roll 20 rotatably attached to the ink roll shaft 41 erected on the frame 1 prints the type 4) 14.
17) Rotate while pressing the type portion 14a and the convex portion 19a formed on the flange portion of the driven boot 9 to apply ink to the type portion 14a. Next, timing pulse detection will be explained with reference to FIG. 5 and FIG. 17.

<Detection of Timing Pulse> Four detection brushes 26 made of a conductive material such as nickel silver are pressed into contact with the detection wheel 24 fixed to the drive pulley 9. A T brush 2BT is placed on the locus of the TP pattern 24a of the conductive part.
The two brushes 26t and 26t are in pressure contact with each other. The number of electrical divisions of the TP pattern 24a is the same as the number of divisions of the driving pulley 9, and is divided into 16, which is one integer fraction of the character position of the character belt 14. When the T brush 26T is in pressure contact with the TP pattern 248L, t brush 2 Q, t is the non-conductive part 24
B is on the TP pattern 242L and the t brush 26T is on the TP pattern 242L.
The T-brush 26T and the T-brush 26t are installed so that the T-brush 2BT is placed above the non-conductive portion 24b when in pressure contact with the non-conductive portion 24b. On the trajectory of the R pattern 24r is the R brush 26R.
are in pressure contact. The detection wheel 24 and the R inspection cam 25 mesh with gears, and each rotation of the detection wheel 24 causes the R inspection cam 25 to rotate 2.5 times. The R-sparing cam 25 is made of a non-conductive material, and the disc portion 25a is interposed between the detection wheel 24 and the R-brush 213R.
and R pattern 24r are blocked. As shown in Figure 5, the R brush 26R and the R pattern 24r are in contact! When the detection wheel 24 rotates once from the time when the R detection cam 25 is 2.5
The rotating R brush 26R cannot come into contact with the R pattern 24a due to the disk portion 25a.

When the detection wheel 24 is rotated one more time, totaling two revolutions, the R detection cam 2
5 rotates a total of five times and returns to the state shown in FIG. 5, and the R brush 28R comes into contact with the R pattern 24a through the notch 25b. Since the detection vehicle 24 was divided into 16 parts, 18X2=32.
The R brush comes into contact with the R butter/ once every 32 positions. The common brush 28c is supplied with ten potentials common to the R pattern 24r and the TP pattern 24a.
The pulse and t pulse waveforms are T brush 26T and t brush 2.
6t vibration and T-bran 2BT and t-brush 26t and TP
Chattering is likely to occur due to contact resistance with the pattern 24a. For this reason, a countermeasure method is adopted in which the rising edge of the leading edge 35a of the pulse 35 is recognized and control is performed using a shaped waveform in which the rising and falling pulses are corrected. A shaping waveform rises at the leading edge 35a of the rising edge of the T-pulse due to the potential difference between the T-brush 213T and the common brush 28c, and a shaping waveform falls at the leading edge 35a of the rising edge of the t-pulse caused by the t-brush 2Ett and the common brush 28c. Control is performed using this shaped waveform created on the side. The shaped waveform in which the R pulse is rising is set as TPO, and the type position 31 (or 63) of the type belt 14 is opposed to the position of the lowest digit, and the type belt 14 is connected to the driving pulley 9 and the driven pulley 19.
Pass the hook between them. The electromagnet energization waveform is the leading edge of the shaping waveform 35
It is controlled by the rising edge of c. The electromagnet is energized at the rising edge of the leading edge 35c of the shaped waveform, and is cut off at the rising edge of the leading edge 35C of the next shaped waveform. The fastest mode for continuous printing is
As shown in FIG. 17, this is a mode in which current is applied at the leading edge of TPO, cut off at the leading edge of TPI, energized at the leading edge of TP2, and cut off at the leading edge of TP3. This embodiment is a cycle machine that prints from the first digit to the most significant digit when printing one line, and then completes the paper feeding process.

Therefore, if the desired printing is 7 digits, it is necessary to selectively print space digits from the 8th digit to the most significant digit. When using this printer for a calculator, it is rare that printing up to the most significant digit is required (the printer is required to have a high printing speed. Therefore, as a means of increasing the printing speed, there are Space positions are set up.

Next, the type selection mechanism will be described.

・　　　　Print selection mechanism〉 This will be explained with reference to FIGS. 1 to 3, FIG. 6, and FIG. 19.

A motor 2 fixed to an injection-molded frame 1 by utilizing the elasticity of the frame 1 rotates in the direction of arrow A. The reduction gear 4 rotates in the direction of arrow B via the motor gear 3, and the transmission gear 5 rotates in the direction of arrow C. In response to the rotation of the transmission gear 5, the sun gear 22 rotates in the direction indicated by the arrow, and the planetary gear 23 rotates in the direction indicated by the arrow E. FIG. 6(9) is an explanatory diagram of the differential mechanism in which the electromagnets are not energized. The planetary gear 23 rotating in the direction of the arrow E applies a rotational force to the printing switching gear 1o in the direction of the arrow H from the internal teeth 10a of the printing switching gear 1o, but the claw 7a of the selection claw 7 rotates through the opening 10b of the printing switching gear 10. , and prevents rotation of the printing switching gear 1o. the result,
The planetary gear 23 revolves in the direction of arrow F along the internal teeth 10a, and the drive pulley 9 rotates in the direction of arrow F. The drive pulley 9 has a groove 9b that engages with the belt teeth 14b of the type belt 14, as described in the above-mentioned section ``Construction of Type Belt'', so that the type belt 14 is reliably rotated in the direction of arrow G without slippage.

The driven pulley 19 reduces the load so that the type belt 14 can rotate smoothly, and the type belt 14 is connected to the platen 17.
It is responsible for running parallel to the When the drive pulley 9 rotates, as explained in Detection of Timing Pulses, repulses are detected by the T brush 2BT, T brush 26t1, common brush 2E3, CNR brush 28R of the detection brush 26, and the desired character part of the character belt 14 is detected. 14
When a reaches, an energizing signal is sent to the electromagnet 6. Figure 6 (
b) is an explanatory diagram of the differential Rh mechanism when the electromagnet 6 is energized. When the electromagnet 6 is energized, a force in the direction of the arrow is generated on the suction plate 33. The selection claw 7 applies a force to the operating portion 7c in contact with the suction plate 33, and a moment is applied in the direction of arrow M.

Moment in the direction of the arrow due to the coil spring 8 and the claw portion 7a
When the moment in the direction of arrow M given by the suction plate 33 becomes larger than the moment of the applied frictional load, the selection pawl 7 rotates in the direction of arrow M. Locking portion 7b of selection claw 7
jumps into the locus of the ratchet 9a of the drive pulley 9 rotating in the direction of arrow F, collides with the ratchet end face 9b, and the drive pulley 9 stops rotating. The planetary gear 23 rotatably attached to the drive pulley 9 stops its revolution around the sun gear 22 and changes to a rotational motion in the direction of arrow E. On the other hand, the print switching gear 10 becomes rotatable because the selection pawl 7 rotates in the direction of arrow M and the pawl portion 7a disengages from the opening portion 10b. The printing switching gear 10 rotates in the direction of the arrow H by receiving the rotation of the planetary gear 23, which has stopped revolution and is rotating in the direction of the arrow E, through the internal teeth 10a. Opening 10b
The claw portion 7a of the selection claw 7 that is disengaged from the cam outer peripheral portion 10
Press c. Gear 1 provided on the outer periphery of the printing switching gear 10
The worm 11 is rotated in the direction of the arrow (■) by the gear flb of the worm 11 that is engaged with the gear 0d.

The number of teeth zlo of the gear 10d of the printing switching gear 10 is set to an integral multiple of the number of teeth zll of the gear flb of the worm 11, and the number of openings 10b of the printing switching gear 10 is set to 210/zll. zl.

=48, zll=12. When the worm 11 rotates once, the opening 10b comes. The claw portion 7 of the selection claw 7 is subjected to a moment in the direction of the arrow by the coil spring 8.
a is the cam outer peripheral portion 10 of the rotating printing switching gear 10;
c, and when the next opening 10b comes, it rotates in the direction of the arrow and engages with the opening 10b. The locking portion 7b is disengaged from the ratchet 9a of the drive pulley 9, and the suction plate 38 is moved in the direction of arrow W. The printing switching gear 10 stops rotating, the planetary wheel 23 begins to revolve in the direction of arrow F, and the drive pulley 9 rotates in the direction of arrow F. The type belt 14 begins to rotate and returns to a standby state waiting for the next energization signal to the electromagnet 6. Next, the printing mechanism will be explained.

<Printing mechanism> Prisoner 4, Figures 7 to 9, Figures 12 to 14, and 19
This will be explained using FIGS. 21 to 21. FIG. 14 is a perspective view of the printing drum 12, FIG. 13 is a perspective view of the hammer 13 unit, FIG. 7 is a sectional view of the standby state before starting printing of the first digit, and FIG. 8 is printing of the first digit. Fig. 9 is a sectional view of the standby state after printing the first digit, Fig. 12 is a diagram of the home position brush state during standby before printing of the first digit, and Fig.
Figure 2 shows the state of the home position brush after printing the first digit. The hammer 18 consists of a suppressing part 1301, an elastic part 13C, and a connecting part 13d, and is integrally molded of plastic, or only the elastic part 13c is insert molded of a metal spring material. The number of hammers 13 is the number of printed digits, and each is connected by a connecting portion 13d.
d is fixed to frame 1. First digit printing will be explained. The home position cam 12d provided on the side surface of the print drum 12 pushes the home position brush 28H, which is made of a conductive material such as nickel silver and is elastically deformed, in the direction of arrow X, contacts the lower position common brush 2θa, and outputs the print drum home position 3 signal. is occurring. Check this signal to confirm that the print drum 12 is in the first digit print standby position. When the desired type portion 14a of the type belt 14 arrives at the first digit, an energizing signal is applied to the electromagnet 6. The worm 11 is rotated by rotation from the print switching gear 10 as described above in the ``Print Selection Mechanism''. The worm tooth 11a is composed of a tooth tip lie, a circumferential ridge lie, and a spiral ridge lid. FIG. 19 is a diagram showing the relationship between the worm teeth 11a of the shaped portion and the pin 12c during standby. The solid line is a developed view of the worm tooth 11a. - The dotted chain line is a perspective view of the worm tooth 11a. During standby, the circumferential protrusion lie of the worm tooth 11a touches the pin 12 of the printing drum 12.
The printing drum 1 is located between the pins 12c in the movement locus of c.
The self-blade rotation of 2 is on the foot side. The lower pin 1 is inserted to prevent the tip of the worm tooth 11a from colliding with the bottle 12c.
2c is the gap S3 between the circumferential protrusion 11c and the lower pin 12c.
In addition, a gap s3 is provided between the tooth tip lie and the upper pin 12c. Warm 11
When the printing drum 12 rotates, the circumferential protrusion 11c that controls the rotation of the printing drum 12 is removed from the tooth tip II before it leaves between the bins 12c.
e falls within the locus of middle 12c. The circumferential protrusion 11C leaves the locus of the pin 12c, and then the pin 12C is lifted by the upper surface 11f of the helical protrusion 11d, and the print drum 2 rotates in the direction of arrow O. The printing claw part 12a installed on the circumference of the printing drum 12 is the pressing part 13e of the hammer 13.
The back surface 13b of is pushed out in the direction of arrow U, and the pressing surface 13a pushes the belt teeth 14b of the type belt 14, which is stopped, to press the type part 14a against the printing paper 16. When the printing drum 12 further rotates in the direction of arrow O, the back surface 1 of the pressing surface 13e
3b and the printing claw part 12a sliding on the back surface 13b are disengaged, and the hammer pressing part 13e is moved in the direction of arrow V by the elasticity of the elastic part 13c of the hammer 13 and returned to the standby position. On the other hand, the home position brush 2 made of an elastic body
The home position cam 12d of the print drum 12, which has been brought into contact with the common brush 26a by elastically deforming the cam 8H, rotates in the direction of arrow O and is disengaged from the home position brush 26H. Disengaged home position “Fern/Brush 26”
H moves in the direction of arrow Y and separates from the common brush 28a. The home position signal' obtained from the home position brush 26H and the common brush 26a is interrupted during printing of the first digit (see FIG. 18). The character selection explained in the above-mentioned "Print Selection Mechanism" and the printing operation described above are repeated from the second digit to the most significant digit. If printing is not necessary, space characters are selected and printed from the character position of the character belt 14. FIG. 21 is an enlarged view of the printed state. FIG. 20 is a partial detailed diagram illustrating the printing position and the position of the comb teeth. The comb teeth 15 are provided on the platen 1, which also serves as a part of the guide, so that the printing paper 16 faces the hammer 13. The comb teeth 15 are injection molded in such a manner that the length thereof extends from the lower part of the printing area 34 through which the character part 14a passes during printing to the vicinity of the upper end 34a of the printing area 34, projecting from the frame 1. The comb teeth 15 are arranged between the print area 34 and the adjacent print area. This will be explained using Fig. wE21. - The chain line indicates the standby position. The hammers 13 held at each print digit are pushed out serially by the rotation of the print drum 12, and the hammers 13 move in the direction of arrow U to press the print portion 14λ against the print paper 16 via the print belt teeth 14b. Since the ink is applied to the printing portion 14a by the ink roll 20, the ink is transferred to the printing paper 16. Comb teeth 15 and printing paper 1
Since the distance 1iliS up to 6 is longer than the height m of the type part 14a, the connecting part 14c of the type belt 14 is connected to the comb teeth 1.
5. The printing portions 14a on both sides of the printing digit cannot approach the printing paper 16 by more than a certain distance to ensure a gap. This will be more reliable if the thickness t of the comb m15 is greater than the height m of the type 14a. Therefore, the structure is such that the type portions 14a on both sides of the print portion 14a in the printing process do not come into contact with the print paper 16. Next, the paper feeding mechanism will be explained.

Paper feed mechanism> This will be explained with reference to FIGS. 10, 11, 12, and 818. ! FIG. 10 is a sectional view of the printing drum after printing the most significant digit. 'M11 is a sectional view during paper feeding. The printing drum 12 has a printing claw part 12a with 13 digits, which is the maximum number of printing digits.
There is. There are 16 pins 12c on the end surface of the print drum 12, and the print drum 12 is rotated by the worm 11 in 15 steps. Two of these steps are used for paper feeding. When the print drum 12 rotates in the direction of arrow O to print the most significant digit (13 digits), a fan-shaped paper feed drive gear 12b provided on the side of the print drum 12 rotates.
rotates in the direction of arrow O until just before it meshes with the paper feed gear 28. After printing the most significant digit (13 digits), the drive pulley 9 rotates and the process moves to the selection process. When an energizing signal waveform is applied to the electromagnet 6 at an arbitrary position, the worm 11i rotates as described above, the print drum 12 rotates in the direction of arrow O, and the paper feed drive gear 12b also rotates in the direction of arrow 0. (Since the printing drum 12 does not have the printing claw portion 12a, the hammer 13 does not move and does not print.) The feed gear 28 receives rotation from the paper feed drive gear 12b and rotates in the direction of arrow Q. A feed roller 29 made of a material such as rubber or soft resin is fitted or two-color molded (insert molded) on a concentric shaft of the paper feed gear 28 and has a diameter larger than the outer diameter of the teeth of the paper feed gear 28. . The feed roller 29 also rotates in the direction of arrow Q. The printed paper 16 pressed against the pressing roller 18, which is subjected to a force due to the elastic deformation of the feeding roller 29 and the pressing shaft 21, is fed by friction in the direction of arrow R. In this embodiment, the desired paper feeding pitch is obtained by two paper feeding operations. Therefore, a signal is given to the electromagnet 6 again to perform the paper feeding operation, and the printing drum 12 returns to the standby position before printing the first digit as shown in FIG.
The print cycle for the line ends. homebojisi 9 link 1
2d pushes down the home position brush 26H in the direction of arrow X to bring it into contact with the common brush 2ea. FIG. 18 is a time chart in which an energizing signal is applied to the electromagnet 6 in the shortest possible time using a paper feed signal. If the next line is to be printed subsequently, the series of operations described above can be repeated.

〔Effect of the invention〕

According to the present invention, since the flange portion of the ink roll side pulley on which the loop-shaped type belt is stretched has a convex portion formed in the same phase position as the type, the difference in blood pressure of the ink roll due to the type is alleviated. This reduces the difference in print density caused by the difference in the amount of ink applied.Furthermore, the vibration stop position of the type belt immediately after type selection is determined depending on whether or not the type grows at the contact position of the ink roll, or the direction of rotation. Even when the pulley is located before or after the flange of the pulley, the influence can be alleviated by the convex portion after the flange of the pulley, so there is an effect that variations can be reduced.

[Brief explanation of the drawing]

Embodiments of the present invention are shown in FIGS. 1 to 21. FIG. 1 is an exploded perspective view of the printer of the present invention. Figure f12 is a schematic configuration diagram of the printer seen from a plane. FIG. 3 is a sectional view of the switching section [8]. FIG. 4 is a schematic side sectional view. FIG. 5 is a back sectional view illustrating the relationship between the detection wheel and the brush. 6th
Figures (a) and (b) are explanatory diagrams of the differential mechanism. FIG. 7 to FIG. 9 are explanatory diagrams showing the printing operation. t410 to 11 are explanatory diagrams showing the paper feeding operation, and FIGS. 12(a) and 12(b) are Baume position/signal explanatory diagrams. FIG. 13 is a perspective view of the hammer. FIG. 14 is a perspective view of the printing drum. FIG. 15 is an explanatory plan view of the type belt. Figure 16 is a diagram of the type arrangement of the type belt. Figures 17 and 18 are time charts. °Figure 19 is a diagram showing the relationship between the printing drum and the worm. FIG. 20 is a partial detailed diagram illustrating the position of the comb teeth. FIG. 21 is an enlarged view of the type belt in the printing position. FIG. 22 is an explanatory diagram of a conventional driven pulley. 1... Frame 6... Electromagnet 7... Selection claw 9... Drive pulley 10... Print switching gear 11... Worm 12... Print drum 13... Hammer 14... Type Belt 15...comb teeth 16...print paper 17...platen 19...driven pulley 19a...convex portion 20...ink roll 22...sun gear 23...planetary gear 24...Detection vehicle 25...R inspection cam 2830. Detection brush 28... Paper feed gear 29... Feed roller 33... Suction plate 40... Follower boo IJ Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 cQ) (b) 12 Eyes 0'-11-N 19th eye 34 34σ Figure 20 Figure 21

Claims (1)

[Claims] A printer having a loop-shaped type belt with type provided on its outer periphery, a pair of pulleys on which the type belt is stretched, and an ink roll that rolls into contact with the type belt to apply ink, wherein the pulley A printer characterized in that a convex portion is formed on the flange portion of the printer at a position in the same phase as the printed characters of the type belt.